Your Android is almost completely full. The SD card is splitting at the seams as it tries to hold all your data. But, you can't uninstall any of your enormous games. Why? Because you'll lose your save files.

Well, put your hands down. A solution is here.

Thanks to a new app called Carbon, you can back up and restore Android app data. It's free, it's easy to use, and you don't need to root your 'droid device to use it.

First things first, you need to download a couple of things. On your Android, grab the free Carbon - App Sync and Backup app from Google Play.

On your computer, get Carbon Desktop. It's free, and works on Windows, Mac, and Linux.

Launch both apps, and then connect your Android device to your computer over USB.

You will be asked to enable USB debugging on your Android. It's supposed to be for development use only, but Carbon needs it to send the backup data to your PC.

Carbon should bounce you to the necessary options screen. If it doesn't, just go into 'settings', choose 'Developer options', and find 'USB debugging'.

If all has gone well, the Android app will now show a list of all the apps you have installed on your device. It's simply a case of picking the apps you want to back up by hitting the checkboxes.

If you choose 'App Data Only' (at the bottom of the screen), Carbon will only keep your save game, and not the app itself. This will make your backup file smaller, but it means you'll need to re-download your apps from Google Play.

When you've picked the appropriate games, hit 'Backup'.

Now, it's time to choose where you want to store your backup file.

Note that most of these options - like Schedule Backup, Dropbox, and Google Drive - only work on the premium version of Carbon.

But, you can back up to your computer for free. Just choose 'USB Storage' while your 'droid device is connected to your PC or Mac.

We're done. You can now delete the game from your Android smartphone or tablet safe in the knowledge that your save game has been backed up.

Okay. We deleted Bad Piggies and then downloaded the app from Google Play again.

Now all you need to do is plug your Android device into your computer, load up the Android app, and choose the 'Restore and Sync' tab. Pick 'USB Storage', or choose the cloud solution you used in step 4.

Tick the apps whose save games you want to recover, and hit 'Restore'. Your save file will transfer from your PC to your Android, and your in-game progress will be restored. Good as new.